SCIENCE NOTES.

Otago Witness, Issue 2558, 25 March 1903, Page 64

SCIENCE NOTES.

— The latest addition to the list of automatic looms is the Walker Continuous lioom, Ihe invention of a firm of Yorkshire manufacturers carrying on the business of weavers of^ worsted coatings at Norwood Green, new Halifax. The Walker 100/ns liave now -been in operation for about a twelvemouth, and a large number of pieces of fine goods woven upon them have been dfaliverec? to the trade. Three looms were turning out worsted serges for the home market, while a fourth — which might be described as semi-au'.omatic — was weaving a woollen-weffrcd pince for the clothing trade. The firm are now fitting up a set of wide cotton-sheeting looms, and also another set of narrow ctlioo looms. Among . the novel features of the Walker Continuous Loom is that of being capable of weaving in two colours, which it is said, no other automatic loom had previously succeeded in doing commercially. Four distinct systems of shuttle-changing are applicable to the jWalkci Continuous 7/Dom. The mechanism may be operated by the failure of weft acting dm the weft-fork, the shuttles can be changed just before the weft is exhausted through J:he vction of a feeler, the changing may be effected by the weaver, or it may bo effected after v predetermined quantity of weft has been woven. "Our object," said Mr Walker to a Leeds Mercury representative the other day, "has been not only lo render greater and cheaper production possible, but to make the operation of weaving easier both to the weaver and to the loom. iYV^itb less wear and tear to the 100m — which, ]i£e many other manufacturers, we prefer to work under maximum specd — we obtain not only a larger, but & more perfect, production." A piece of shepherd tartan, or black and white checked plaid, of fine .worsted, .voven on the new loom, proved to our representative the justness of the claim. Two women weavers wero attending to the four looms in operation, but Mr Walker explained that the number of operatives was simply a question of the class of goods — or the time, dependent on the class of yarn, which one spool remains in the loom. One weaver might attend to four looms weaving summer goods. For all classes of goods one weaver might disohargo double the duty ot present performed. The invention, which is about to be exploited for the Walker Continuous Loom Syndicate (Limited), is capable of being adjusted to any extant loom, and v there are nearly three-quarters of a million now in operation in the United Kingdom — 100,000 in the worsted and woolJen trades alone— there is a wide field in which to test its utility. — Professor Gregory tells the readers of the Cornhill Magazine that the future of -astronomy lies with the dark stars rather than -with those with luminous radiations. So far ac investigations have been carried, it is proved that one star in every six has near it a black star — a star as invisible to the telescope as to the most sensitive photographic films. — At the recent Sanitary Congiess held in Manchester, Sir Jamos Crichton-Browne dealt in an exhaustive manner with the subject of dust. "We are," he said, "from the cradle to the gra\e encompassed by a cloud of dust" ; und then he proceeded to bliow the various sources from which the different kinds of dust had their origin. Part of it comes to us from space in tie form of meteoric dust. Every shooting st;ir which wo Ece slanting across the sky breaks up and finds its way as dust to our earth. The volcanoes, as wo have all been recently reminded, send forth dust by thousands of tons. In the healthiest places we find dust —200 particles have been counted in a cubic centimetre; and in London Uip number totals up to 150,000 particles. The greater the number the more- disease ; and this quite apart from any question of pathogenic ferms. fhe dust of cities is made up of all kinds of incompatible items, such as eand, soot, salt, cotton fibres, vepretable debris, pollen of flowers and grasses, bits of Btraw, scales of skin, and other organic and inorganic fragments. Then in certain localities there are deadly ingredients added to tbe ordinary dust: tiny particles of kad which bring death to the workers in many trades, arsenical dust which affects others, phosphorus dust whic! attacks the ma'c.imakeis. and the terrible anthrax dust wh'ch brings "wcol-scrters' disease." fhni ilicrc is 'the gritty du=t which wears down t!.c lungs by- its irritating presence, and which is constantly present in other manufactures. With all thee minute cn n raiM varr'.nsj against v' in thr- an- we br<\it'-o i' is a matter for wondr-r that the general l'"-*.i-ra%c is rs low a> il ;s.; s. . —To burn bitunvrous real without =iv.o\"> (sajs the Locomotive) has long been the hoofl of inventora «ud eaidoe«ri» lot it is.

generally admitted that an enormous waste occurs when any considerable amount of smoke issues from the chimney. It is true that smoke is a ture indication of imperfect combustion, but the vapour ordinarily seen coming from the chimney is not all smoke. The dense black smoke sometimes seen cotifaists almost entirely of unconsumed carbon, but the composition of the lighter smokeis very different. Most coa' contains a considerable quantity of moisture, especially bituminous coal ; and this moisture is, of course, evaporated by the heat of the fire and driven off as steam in company with other products of combustion, giving the light -vapour usually seen issuing from the chimneys. Even the densest smoke contains but a small quantity of unconsumod carbon, as measured in pounds, though it is likely to contain a considerable quantity of invisible gases that would have be'en burned and utilised had the combustion been more perfect. The black smoke is usxially given off when long flames of a yellowish or reddish hue lap along the whole length of the boiler, and >perhaps pass into the flues. When the damper is right, the draught good, and Jie fires are well laid, so that all parts of the grate are evenly covered, the lazy, smoky flame is changed to a short flame of intense brightness. Too much air is as cabable of producing smoke as too little; for by its dulling action it makes perfect :ombustion impossible, and causes the same dense cloud to appear at the stack. — The current number of Nature contains an account of Dr Lyster Jameson's researches into the origin of the pearl. . . . There is a worm in the pearl as well as in the bud. ... It begins life — in its lowliest form— a mere germ-creature in the common cookie, or sometimes in the hardly less abundant tapestry shell (Tapes decussatus). There it remains till it reaches the larval stage. It then escapes, floats with the current till it drifts against a living mussel or other pearl-making shell. It promptly pierces through the body-wall, and settles down in its new home. Its unwilling "host" resents the intrusion, first by enclosing it in a sort of bag, and then with shelly material. So the pearl is the intruder's grave and monument— and the beauty of the lattei, as sometimes happens in human history, ■ is greater than the merits of the person commemorated. — Standard. — One of the troubles against which electric transmission on the Pacific slope has to contend is, it seems, fog. From Santa Monica, California, there is a transmission line extending for several miles along a coast that is subject to thick fogs. It has been found that the electric lines work well in wot weather; but with a dry spell, followed by a fog, poles would become burned orF, this probably taking place first by the turning of an insulator pin, followed by the cross arm, which would allow the wire to swing against the pole. According to a writer in Page's Magazine, the trouble i.s attibutcd to dust collecting on the underside of the petticoats of the insulator, to the formation of a paste by the moistening of the dust, and to the final leakage of current through the paste. To overcome this dim- I oulty, the pins and the lower part of the insulators are buried in a red wood block 4£in deep, with the hole for the- insulator of ljin greater radius than the insulator, and the top of the block 2in below the wire. So far, it is said, the device has prevented dust and fog drifting in under the insulator. —Dr Sven Hedin, who is now visiting various European capitals and giving an account of his latest explorations in Central Asia, has now definitely completed the arrangements for the publication of the scientific results ot his great journey. The Swedish Government has undertaken to make a considerable contribution towards the cost of publication, and has agreed that the work shall be printed in English. The •object in selecting English as tho medium of giving the scientific results of Dr Hcdin's expedition to the world is twofold. In the first place, it is recognised that those results will bo much more accessible to scientists generally than if they were published in Swedish, and, in the second place, it is hoped that a larger number of mdi. viduals and learned societies will subscrilv> for copies of the work than if it wore published in any other European language. Ojtr interests in Central Asia arc incomparably jrreater than those of any other European Power except Russia, and Russian was, of course, impossible as a medium of nmmunication with the fcientific world. Oarcful estimates have been prepared of the total cost of the four or five quarto volumes of text and the. two folio volumes of wap=. and it is calculated that the entire work will cost the Swedish Government about £4200. It is proposed to limit the pdition to 250 sr-ts, aud the subscription rrice has been fixed at £15 the set. Dr Hedin, the value of whose labours has be^n enthusiastically recognised by Lord C'irzon, hopes that the Swedish Governnipnt. which has no direct interests in Central A-ua. may be recouped a considerable port'on of its outlay by the subscriptions from this country and from India. Some idea of the amount of labour involved and of th» extraordinary vahi" of the ma( r nnl« ro'!rci.'d by Dr TTc'in may bo pat herd from the fr.rt that in (lie course of hi« ihree. vpt-»' c\plornt!on<s he traversed a distance or about 6500 miles, ovrry st^p of t'l* v.ay I'd". 7 ma)ir""d on the '(.lie of 1 : 5i 003. Th° (n:i 'jMniiicil work wa« r-mbo.iied i" no l^ss than 11 J 9 mans, and to r'.-.Pt'c lis rv; ;:rr '■i.f the loe:»l yio irici-> rer c II." n"-f--i \:r\" Arlrr-a ned aatroncmica'lv. T k tvi-i" ff cr. ; io^ranhicil nr»t«riil will h n reduced V>v t lno """"T'i! ' 1- >ff eif tii" S"-c.-'i-'\ a r irv in i' 1^ Lul'^ir •!ili o I T'i-t'tMl» •- cVr'-'-^'.:"c Vr'-'-^'.:" to il - -.'p ~f 1: jin OCO a' 1 :l'e 'no of 1: 200 000. A numI hn- of Dr B>rlhi'<: or'.jr'.nM ivm s will Imj I reproduced, and in the volume of text which J will iccomsanx the sUm there xillJtt.j>tiiS£

maps and come 500 illustrations by Dr Hedin, who, in addition to his many other qualifications, is an accomplished artist. Arrangements have also been made for the publication of a special volume dealing with the meteorological observations of another dealing with the astronomical observations, and of a third describing the geological, botanical, and zoological collections. All these volumes will be edited by recognised experts, and will be profusely illustrated, while an additional volume by Dr Himly, of Wiesbaden, tho well-known Chinese scholar, will deal with the Chinese manuscripts and inscriptions of the third century of our era which were discovered by Dr Sven Hedin amid the ruins of the old Chinese town that stood on the shoro of the now desiccated lake of Lob Nor.— Field. February 7. —In aeronautical engineering (says the Engineering Magazine), where lightness, strength, and stiffu-ess must be united, and in which the maximum amount of motive power is carried and transmitted within the minimum -limits of weight, the highest degree of ability in the disposition and use of materials of engineering is demanded. With these, is involved a knowledge of the principles of equilibrium, since the questioning of balancing enters into problem to a controlling extent. Under such circumstances it is 'almost criminal to permit ascensions to be mado in machines in which such radical defects exist, and If experiments fn aeronautics are to be continued, some sort cf general inspection should be required to prevent the needless exposure of human life. In this connection attention may be called to a plan which has been proposed to develop the possibilities of the aeroplane, which is generally admitted to possess greater scientific possibilities than any form of dirigible balloon. If an aeroplane, consti noted upon such scientific lines as the machines of Lan^ley or of Maxim, were supported by a dirigible balloon, it might be altogether possible to obtain such a degree of experience in its manipulation as to allow the degree of support to be gradually diminished, and finally withdraw altogether. The operation would resemble the use of the inflated belt in swimming instruction, the belt being gradually deflated as the pupil gains proficiency. In some such experimental way as this the dirigible balloon may add to our stock of knowledge in aeronautical engineering, otherwise there ?ecms to be little use. in continuing 1 experiments in which there is so much to lose and so little to gain.